通过命令提示符运行的JDBC Java文件

Question

I have created a java gui within Netbeans and am now attempting to run it through Command Prompt using the java -jar [filename].jar command.

The gui I have created connects to a database (also created within the Servers section of Netbeans). The database is connected to view the jdbc:derby://localhost:1527/[DBName] command. It also takes in the user name and password and then connects.

My issue is, I can connect within Netbeans (obviously I have to find the database in the Services tab first and connect to it) but I can't connect to the database in command prompt.

With the completed code I have selected 'Clean and Build' in Netbeans to create the .jar file in the /dist folder.

I can run the .jar file but it returns an error stating: java.net.ConnectionException : Error connecting to server localhost on port 1527 with message Connection refused: connect.

My /dist folder contains the .jar file for the application as well as a README.TXT file and a /lib folder, which itself contains the derbyclient.jar file.

When creating my database I set the location as the java project directory so within the java project directory I have a /[DBName] folder that I assume contains my database.

How do I connect to the database in command prompt? Or at least allow my program to do so?

Do I have to explicitly declare the location of my database?

Do I need to export the database from Netbeans somehow?

Any help would be great. I'm toying with Java at the moment and wanted to know how to run it in command prompt, completely standalone from any IDE's.

J

Answer 1

Derby has a command line client called ij that you can use to type SQL commands. If you are using the derby that is built into the java distribution then you need to look under JAVA_HOME/db/bin and you will find a lot of .sh and .bat files to start up the derby server,

NetworkServerControl     derby_common.bat         setEmbeddedCP.bat        setNetworkServerCP.bat   stopNetworkServer.bat
NetworkServerControl.bat ij                       setNetworkClientCP       startNetworkServer       sysinfo
dblook                   ij.bat                   setNetworkClientCP.bat   startNetworkServer.bat   sysinfo.bat
dblook.bat               setEmbeddedCP            setNetworkServerCP       stopNetworkServer

so look at those files and read the docs for the java derby db to see how to start it. Calling startNetworkServer will start derby as a network server on port 1527.

http://db.apache.org/derby/ contains a lot of docs on derby.